This is a work in progress, but a couple people wanted it so here it is! I also don't know what I'm doing so my model is probably terrible.
You only need to use supports for the posts that stick out of the right half of the tray and the cavities those posts go into on the left half.
This model needs 4 M6 screws and 4 nuts to work with how I have it set up. Two to connect the two halves and two to mount it to your rig.
I have added a grid of mounting holes, the holes are spaced 20mm by 40mm through the length of the tray and should be fairly easy to mount to aluminum profile, or your own solution.
I have also removed some material to save filament and made the phone holder a little deeper and gave it a 30 degree tilt (it was 15).
The file is in two pieces and will print on a 220x220mm bed.
The author marked this model as their own original creation.